Just made my first attempt at the Lebanese and Greek garlic sauce recipes I found online, and I'd be willing to bet Beck Hansen's Hyundai that I've found the recipe for Zankou's mystery garlic sauce.
Here's what I did (I dedicate this one to Jenny and her sister, I think her name is Debra):
Peel three small russet potatoes and boil in water until soft. Mash the potatoes (I used a food mill) and let cool.
Crush and peel a whole head of garlic (about 12 large cloves). Cut into quarters. Place raw garlic in a heavy duty blender (I used a 390-watt Waring) with 1/2 tbsp. of salt and juice of two large lemons (about 1/3 cup). Pour 1/2 cup of oil (I used canola oil) into a measuring cup and pour a small amount of oil from cup onto garlic (just enough for a light layer). Puree the garlic, salt and lemon juice on "Hi" and begin pouring a slow, steady stream of oil through the blender's handle hole until everything has coalesced.
At this point the sauce looked pretty damn good. I took a taste and it was a potent blast of pure garlic satisfaction. I would have stopped here, but I was after that elusive Zankou taste and texture, so on come the potatoes.
Add the mashed potatoes, about 2-3 tablespoons at a time. Add more potato after the sauce becomes consistent, and keep adding until all is incorporated in the sauce. You might want to transfer the garlic paste to a mixer before this step and add the potatoes in the mixer as my Waring was starting to show signs of stress towards the end of this process.
Transfer to a bowl and allow to cool completely in the fridge. After about an hour the flavors will blend together nicely and the texture will take on that library paste consistency like Zankou's sauce. Fortunately I had smoked chicken left over from last night's barbecue, so I heated it up in the oven and used it a "delivery medium" for the garlic sauce. It was just like Zankou. I bet it will be even better tomorrow.
I even gave this Sonia's frying test. The sauce held together in the frying pan, even as it started to sear and transform into some sadistic latke.
Here are the ingredients again in an easier to read format:
-3 small russet potatoes
-1 head of garlic (12-14 cloves)
-1/3 cup of fresh lemon juice
-1/2 tbsp. salt
-1/2 cup canola oil